In recent years there have been developments in the art of computerized teaching of speech. Speech laboratories in which prompts and cues such as pre-recorded sounds and words are presented to a student and the students' speech productions are recorded or monitored are well known.
The Speech Viewer II, marketed by IBM, is a speech therapy product which provides visual and auditory feedback from a student's sound productions.
Known methods and apparatus for computerized speech recognition are described in the following publications, the disclosures of which are incorporated herein by reference:
Flanagan, J. L. "Computers that talk and listen: Man machine communication by voice", Proc IEEE, Vol. 64, 1976, pp. 405-415;
Itakura, F. "Minimum prediction residual principle applied to speech recognition", IEEE Trans. Acoustics, Speech and Signal Processing, February, 1975-describes a temporal alignment algorithm and a method for computing a distance metric;
Le Roux, J. and Gueguen, C. "A fixed point computation of partial correlation coefficients", IEEE ASSP, June, 1977;
Peacocke, R. D. and Graf, D. H, "An introduction to speech and speaker recognition", IEEE Computer, Vol. 23(8), August, 1990, pp. 26-33;
L. R. Rabiner et al, "Speaker-independent recognition of isolated words using clustering techniques" IEEE Trans Acoustics, Speech and Signal Processing, Vol. ASSP-27, No. 4, August, 1979, pp. 336-349;
L. R. Rabiner, Levison, S.E. and Sondhi, M. M., "On the application of vector quantization and hidden Markov models to speaker-independent, isolated word recognition", Bell Systems Tech J, Vol. 62(4), April, 1983, pp. 1075-1105;
L. R. Rabiner, and Sambur, M.R., "An algorithm for determining the endpoints of isolated utterances", Bell Systems Tech J, February, 1975;
L. R. Rabiner, and Wilpon, J. G., "A simplified, robust training procedure for speaker trained isolated word recognition systems" J Acoustical Society of America, November, 1980.
The disclosures of all the above publications are incorporated herein by reference.